Caffeine affects the effects of drugs, be careful with your medication

There are many coffee shops in the streets and alleys. Whether it is to refresh yourself at work or to socialize, drinking coffee has become an indispensable part of daily life. According to statistics, people around the world drink about 6 billion cups of tea every day, and the consumption of coffee is astonishing. Taiwanese people alone drink up to 2.1 billion cups of freshly brewed coffee every year. Have you ever thought that these drinks are inseparable from our lives, and the caffeine they contain may affect the effect of medicines?

Caffeine is the most popular psychoactive substance in the world. This alkaloid is commonly found in coffee beans, tea leaves, and cocoa beans. It can stimulate the cerebral cortex to refresh the mind, and also has a slight bronchial dilation and diuretic effect. It also acts on the myocardium and blood vessels. In addition to coffee and various teas, other products on the market include energy drinks, carbonated drinks, chocolate, and even many medicines, such as commercial cold medicines and painkillers. These ubiquitous caffeine is often overlooked by everyone, but its multiple physiological effects and special metabolic mechanisms may interact with certain drugs. Especially those who consume a lot of caffeine every day should be especially careful.

Taking psychiatric medication as an example, high doses of caffeine will reduce the blood concentration of lithium salts, a mood stabilizer. If caffeine is stopped suddenly, the blood concentration of lithium salts may rise, increasing the risk of lithium poisoning. In addition, caffeine is metabolized by the liver enzyme CYP1A2. If it is used with drugs that are also substrates of CYP1A2, it will affect the efficacy of the drug. For example, the psychotropic stabilizer clozapine, if used with caffeine, may increase its blood concentration by up to 60%. Caffeine also antagonizes the effects of benzodiazepines, a sedative hypnotic. If caffeine is taken in large quantities, it is easy to cause anxiety and insomnia.

Director Zheng of the Pharmacy Department of Taoyuan Sanatorium of the Ministry of Health and Welfare reminds the public that when seeking medical treatment or purchasing over-the-counter drugs at a pharmacy, they must proactively inform the doctor or pharmacist of their usual caffeine use. When taking medicine, it is best to drink warm water. Be careful of the caffeine that is everywhere around you!